檢查字符串是否為空或null或僅僅包含空格
  String test = "";
  String test1=" ";
  String test2 = "\n\n\t";
  String test3 = null;
  System.out.println( "test blank? " + StringUtils.isBlank( test ) );
  System.out.println( "test1 blank? " + StringUtils.isBlank( test1 ) );
  System.out.println( "test2 blank? " + StringUtils.isBlank( test2 ) );
  System.out.println( "test3 blank? " + StringUtils.isBlank( test3 ) );
  運行結(jié)果：
  test blank? true
  test1 blank? true
  test2 blank? true
  test3 blank? true
  相對應(yīng)的還有一個StringUtils.isNotBlank(String str)
  StringUtils.isEmpty(String str)則檢查字符串是否為空或null（不檢查是否僅僅包含空格）
 
  分解字符串
  StringUtils.split(null, *, *)            = null
  StringUtils.split("", *, *)              = []
  StringUtils.split("ab de fg", null, 0)   = ["ab", "cd", "ef"]
  StringUtils.split("ab   de fg", null, 0) = ["ab", "cd", "ef"]
  StringUtils.split("ab:cd:ef", ":", 0)    = ["ab", "cd", "ef"]
  StringUtils.split("ab:cd:ef", ":", 1)    = ["ab:cd:ef"]
  StringUtils.split("ab:cd:ef", ":", 2)    = ["ab", "cd:ef"]
  StringUtils.split(String str,String separatorChars,int max) str為null時返回null
  separatorChars為null時默認(rèn)為按空格分解，max為0或負(fù)數(shù)時分解沒有限制，max為1時返回整個字符串，max為分解成的個數(shù)（大于實際則無效）
 
  去除字符串前后指定的字符
  StringUtils.strip(null, *)          = null
  StringUtils.strip("", *)            = ""
  StringUtils.strip("abc", null)      = "abc"
  StringUtils.strip(" abc ", null)    = "abc"
  StringUtils.strip("  abcyx", "xyz") = "  abc"
  StringUtils.strip(String str,String stripChars) str為null時返回null,stripChars為null時默認(rèn)為空格

  創(chuàng)建醒目的Header（調(diào)試時用）
  public String createHeader( String title ) {
    int width = 30;
    String stars = StringUtils.repeat( "*", width);
    String centered = StringUtils.center( title, width, "*" );
    String heading = StringUtils.join(new Object[]{stars, centered, stars}, "\n");
    return heading;
  }
  調(diào)用createHeader("TEST")的輸出結(jié)果:
  ******************************
  ************ TEST ************
  ******************************

  字符的全部反轉(zhuǎn)及以單個詞為單位的反轉(zhuǎn)
  String original = "In time, I grew tired of his babbling nonsense.";
  StringUtils.reverse( original )   = ".esnesnon gnilbbab sih fo derit werg I ,emit nI"
  以單個詞為單位的反轉(zhuǎn)
  public Sentence reverseSentence(String sentence) {
    String reversed = StringUtils.chomp( sentence, "." );
    reversed = StringUtils.reverseDelimited( reversed, ' ' );
    reversed = reversed + ".";
    return reversed;
  }
  String sentence = "I am Susan."
  reverseSentence( sentence ) )   = "Susan am I."

  檢查字符串是否僅僅包含數(shù)字、字母或數(shù)字和字母的混合
  String test1 = "ORANGE";
  String test2 = "ICE9";
  String test3 = "ICE CREAM";
  String test4 = "820B Judson Avenue";
  String test5 = "1976";
  結(jié)果：
  boolean t1val = StringUtils.isAlpha( test1 ); // returns true
  boolean t2val = StringUtils.isAlphanumeric( test2 ); // returns true
  boolean t3val = StringUtils.isAlphaSpace( test3 ); // returns true
  boolean t4val = StringUtils.isAlphanumericSpace( test4 ); // returns true
  boolean t5val = StringUtils.isNumeric( test5 ); // returns true